Development of a Biomimetic Hydrogel Based on Predifferentiated Mesenchymal Stem-Cell-Derived ECM for Cartilage Tissue Engineering.

The use of decellularized extracellular matrix (dECM) as a biomaterial has been an important step forward for the development of functional tissue constructs. In addition to tissues and organs, cell cultures are gaining a lot of attention as an alternative source of dECM. In this work, a novel biomimetic hydrogel is developed based on dECM obtained from mesenchymal stem cells (mdECM) for cartilage tissue engineering. To this end, cells are seeded under specific culture conditions to generate an early chondrogenic extracellular matrix (ECM) providing cues and elements necessary for cartilage development. The composition is determined by quantitative, histological, and mass spectrometry techniques. Moreover, the decellularization process is evaluated by measuring the DNA content and compositional analyses, and the hydrogel is formulated at different concentrations (3% and 6% w/v). Results show that mdECM derived hydrogels possess excellent biocompatibility and suitable physicochemical and mechanical properties for their injectability. Furthermore, it is evidenced that this hydrogel is able to induce chondrogenesis of mesenchymal stem cells (MSCs) without supplemental factors and, furthermore, to form hyaline cartilage-like tissue after in vivo implantation. These findings demonstrate for the first time the potential of this hydrogel based on mdECM for applications in cartilage repair and regeneration.